Method for the management of fluids required for the operation of a vehicle and device making it possible to implement it

ABSTRACT

The invention relates to a method for the management of fluids required to operate a vehicle, remarkable in that it comprises an operation of the anodic oxidation of a solution of hydrogen peroxide (P) for the purpose of producing oxygen, water and hydrogen cations by subjecting said solution to an electric current produced by an electrical power source. 
     The invention also relates to a device that makes it possible to implement the method. 
     Applications: management of the fluids required to operate a vehicle in particular an aircraft.

FIELD OF APPLICATION OF THE INVENTION

This invention relates to the field of the management of fluids requiredto operate a vehicle such as an aircraft and in particular to theadaptations making it possible to supply, produce, store, consume,evacuate said fluids in the best conditions.

DESCRIPTION OF PRIOR ART

In the framework of the operation of a vehicle such as an aircraft, aplurality of fluids has to be managed by the operator.

As such, for example, it is necessary to supply pure oxygen to thepassengers of an aircraft in particular in the event of adepressurisation of the cabin. This making available of oxygen is donefor a limited number of minutes, the time to allow the aircraft todescend to an altitude that does not require pressurisation. Thesupplying of this oxygen requires storing it or the storing of theproducts that participate in producing it. This storage defines a spaceand a weight that requires the availability of a volume and a supply ofenergy for the aircraft.

Another fluid required for the operation of an aircraft carryingpassengers is drinking water. This water is conventionally loaded on theground which requires a substantial volume of storage and defines aweight that is also substantial. This storage therefore defines a spaceand a weight that consume energy at take-off and in flight. Theprocurement in water also comes up against the problems of the qualityof the water which does not have the same criteria according to thecountry (having for example different proportions of bacteria and/orscale).

A scaling of the coffee-making devices can require the stoppage of theaircraft and a costly maintenance operation.

The possible presence of bacteria requires the water consumed to betreated. However, the known systems that use chlorine and/or theproduction of ultraviolet rays only have a relative degree ofeffectiveness. The storage and the distribution of water treatmentproducts require a volume and energy that can have costs.

In addition, if good treatment of the water consumed can finally beachieved, the same does not apply to the pipes. Treating the drinkingwater network requires immobilising the aircraft and therefore has acost for its operator.

Other fluids that may have to be managed in the framework of operatingan aircraft as well as in that for a vehicle in general (in particularvehicles with wheels) are those required for the operation of a fuelcell. These devices produce electrical power as a substitute at leastpartially for batteries. These devices have the advantage of having abetter output than that of batteries while still not producing nitrogenor carbon monoxide. These devices also have for advantage to allow forthe production of water.

However, these devices also have several disadvantages of which thoserecalled hereinbelow:

-   -   they can release a substantial amount of heat,    -   fuel cells that operate with hydrogen require the storage of the        latter either filled when the aircraft is on the ground, or        produced in flight by water electrolysis which requires more        power than a fuel cell can produce;    -   Fuel cells that operate with oxygen require the latter to be        stored;    -   The water, which is produced only in a small (insufficient)        quantity, requires remineralisation before it is consumed which        requires an additional device;    -   The reversibility of such devices consumes more power than they        produce,    -   etc.

In order to resolve the problems of overvoltage and of the production ofheat and in order to be released from the constraint of the presence ofoxygen, it is known to use hydrogen peroxide as a substitute by carryingout the reduction of the peroxide into hydroxide OH⁻ion.

However, reducing the peroxide does not solve all of the problems withrespect to the fuel cell or with respect to the management of the otherfluids.

DESCRIPTION OF THE INVENTION

Observing this, the applicant carried out research aimed at providing asolution to the disadvantages described hereinabove. This researchresulted in the designing and the carrying out of a method for themanagement of fluids required for the operation of a vehicle not only ofthe aircraft type but also any type of vehicle that uses electricity.

According to the main characteristic of the invention, the method forthe management of fluids required to operate a vehicle, is remarkable inthat it comprises an operation of the anodic oxidation of a solution ofhydrogen peroxide for the purpose of producing oxygen, water andhydrogen cations by subjecting said solution to an electric currentproduced by an electrical power source.

This characteristic is particularly advantageous in that it makes itpossible, based on a single fluid subjected to an electric current, tohave via a single operation of oxidation at least two fluids required(or able to be required) for the operation of a vehicle such as anaircraft.

As such, the anodic oxidation of a solution of hydrogen peroxide leadsto the obtaining of the following elements:

-   -   oxygen O₂ coming from the separation of the molecule of oxygen        from that of dihydrogen burst into two hydrogen ions,    -   a remainder of hydrogen peroxide H₂O₂ not broken down,    -   water H₂O coming from the solution.

The circulation of the water coming from the solution makes it possibleto remove the heat from the reaction. The hydrogen cations are not usedin this first phase.

The oxygen produced will make it possible to propose the makingavailable of this gas for the aircraft. As such, it appears that theoxygen will be able to be produced on demand and in a large quantity.This production of oxygen is combined with the decrease in theconcentration of hydrogen peroxide in the water solution, which makes itpossible to have a large volume of water. This water is therefore oncemineralised not only drinkable but also treated due to the biocideproperties of the remainder of peroxide.

The production of a treated water resolves the various problems linkedto its quality and to the maintaining of the drinking water network ofthe aircraft.

This characteristic as such defines a phase of the method whichcomprises an operation of filling with a solution of hydrogen peroxide atank carried by the vehicle. The concentration of hydrogen peroxide inthe solution is according to a particularly advantageous characteristicof the invention, between ten and seventy percent.

According to a particularly original phase of the method, the lattercomprises an operation of filling the drinking water tank provided onthe vehicle with a solution of hydrogen peroxide. As such, the solutionof hydrogen peroxide is stored in a volume replacing that of the oxygenbut also that of the drinking water. Said tank receiving the hydrogenperoxide is then provided with a safety valve.

Said tank can also be rendered passive or be manufactured from aluminiumin order to prevent the disproportionation described hereinabove.

According to a particularly advantageous embodiment that avoids havingto replace stainless steel tanks and pipes already available on anaircraft, the solution of hydrogen peroxide is stabilised by addingmetal sequestering agents at the trace state (very small quantity).

The space and weight saved are substantial and satisfy the objectives ofthe invention.

According to another characteristic, the method consists in mineralisingthe solution of hydrogen peroxide, which avoids the need for aremineralisation cell or makes it possible to undersize it.

The electrical power of the electrical power source required for theanodic oxidation of the hydrogen peroxide comes from batteries or excesselectricity available during takeoff and during the flight at a cruisingspeed of the aircraft.

As such, based on the single solution of hydrogen peroxide, theinvention proposes the production of two fluids required for theoperation of an aircraft, namely oxygen and water.

This anodic oxidation is differentiated from the disproportionationknown for the peroxide which does not produce hydrogen ions H⁺.

According to another characteristic of the invention, the methodcomprises an operation of the cathodic reduction of the hydrogen cationscoming from said operation of anodic oxidation for the purpose ofproducing dihydrogen.

This first phase of the method further comprises an operation of storingthe hydrogen produced. This storage is carried out in the vehicle. Thishydrogen will be able to be used in the framework of a second phase ofproducing electricity still by using the same solution of hydrogenperoxide stored, not as a reducer but as an oxidant in order to form afuel cell. As such, according to another particularly advantageouscharacteristic, the method comprises an operation of oxidation of thehydrogen produced combined with an operation of reducing the hydrogenperoxide for the purpose of producing electricity and water. Thequantity of electricity produced is greater than that required for theanodic oxidation.

This fuel cell can be implemented by an independent cell or by theinversion of the cell that produced the hydrogen. As such, the method ofthe invention proposes in addition to producing oxygen and water, toprovide for the production of the electricity required for the operationof the aircraft at least partially. The carrying of the solution ofhydrogen peroxide in the aircraft thus becomes a global solution to theproblem of storage, weight and production of power for the aircraft.

As explained hereinabove, the use of hydrogen peroxide makes it possibleto produce in a first phase the hydrogen required in a second phase forthe production of electricity. These two steps can be applied to anyvehicle that is able to have its peroxide tank supplied on a regularbasis. Indeed, the power required to produce hydrogen using hydrogenperoxide is less than the power produced by a fuel cell using thehydrogen/hydrogen peroxide pair. Such a vehicle would then have asubstantial degree of autonomy without producing any exhaust gas otherthan water vapour which itself can be recovered. Such a method comprisesan operation of neutralising the peroxide still present in the water.This recovered water could return to the volume of initial storagecompartmented for this purpose.

In order to suppress any impurities present in the oxygen obtained, themethod comprises an operation of treating the oxygen produced.

In addition, if the method comprises an operation of remineralising thewater produced, the latter is not as substantial than if the water hadonly come from a cell of the fuel cell type since in the first phase ofthe method, according to a characteristic described hereinabove, thewater of the peroxide solution is mineralised.

The invention also relates to the device that makes it possible toimplement the invention.

For example, the device comprises an oxidation cell that, comprisingsaid electrical power source, is provided with an anode wherein saidoxidation takes place and with a cathode separated by a cationicmembrane that allows only H⁺ ions to pass, with the positive pole of thesource of power being connected to the anode.

This characteristic avoids polluting the cathode by the presence ofother ions coming from the minerals contained according to acharacteristic described hereinabove in the solution of hydrogenperoxide.

More precisely, this cell comprises one or several membranes of thecationic type separating two electrodes:

-   -   a cathode connected to the − pole,    -   an anode connected to the + pole of a generator.

According to another particularly advantageous characteristic of thedevice, said anode comprises several couches:

-   -   a first porous layer containing a catalyst for producing the        anodic oxidation e⁻ electrons,    -   a second porous layer containing a catalyst for capturing anodic        oxidation electrons, and    -   a non-porous electrical conductor electrically insulated on the        face in contact with the first layer and on the face in contact        with the hydrogen peroxide.

As such, the anode of the oxidation cell contains catalysts that arespecific to the acceleration of the anodic oxidation allowing for a fasttransfer of the ions and of the electrons. These catalysts can be onseveral layers.

According to a preferred but not limited embodiment, the anode cancontain a porous membrane made of gold or supported by a porous membranemade of platinum.

The fundamental concepts of the invention now exposed hereinabove intheir most basic form, other details and characteristics shall appearmore clearly when reading the following description and with respect tothe annexed drawings, provided as a non-restricted example, anembodiment of a method in accordance with the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagrammatical drawing of an embodiment of an implementationaboard an aircraft of the first phase of the method of the invention;

FIG. 2 is the diagrammatical drawing of FIG. 1 showing an embodiment ofan implementation of the second phase of the method of the invention;

FIG. 3 is a detailed diagrammatical drawing of an embodiment of theanodic oxidation cell used for the first phase of the method;

FIG. 4 is a detailed diagrammatical drawing of an embodiment of the fuelcell used for the second phase of the method;

FIG. 5 is a diagrammatical drawing showing an embodiment of a circuitimplementing the two phases of the method for a land vehicle.

DESCRIPTION OF PREFERRED EMBODIMENTS

As shown in the drawing of FIG. 1, the aircraft A is provided with adevice that makes it possible to implement the method of the invention.

This device comprises a tank 100 wherein is stored hydrogen peroxide P.This tank 100 comprises a safety valve 110 as well as a conduit 120allowing it to be filled from the outside. Another conduit 130 makes itpossible by using a pump 140, to convey said peroxide into an anodicoxidation cell 200 which is associated with an electrical power source210.

As shown in FIG. 3, the electrical actuation makes it possible usingperoxide H₂O₂ (solution of hydrogen peroxide containing H₂O₂ and H₂Osymbolised by the arrow F1) to obtain hydrogen ions H⁺ from theelectrons e⁻ and oxygen O₂ according to the following reaction:

H₂O₂→2H⁺+2e ⁻+O₂

The results of this reaction are oxygen O₂, water H₂O coming from theperoxide solution and hydrogen peroxide H₂O₂ that was not oxidised andtherefore at a lower concentration. This result is symbolised by thearrow F2.

The anodic oxidation is obtained by means of a particular anode 220 thathas several layers, among these:

-   -   a first porous layer 221 containing a catalyst for producing        anodic oxidation e⁻ electrons,    -   a second porous layer 222 containing a catalyst for capturing        anodic oxidation electrons.

The anode also comprises a non-porous electrical conductor insulatedelectrically on the face in contact with the first layer and on the facein contact with the hydrogen peroxide.

In addition, the face in contact with the hydrogen peroxide is treatedin order to prevent the parasitic breaking down of the latter.

The first layer and the second layer form a catalytic dipole. Thematerials of these layers are chosen in such a way that in the absenceof a connection of the cell to an electric generator, the electricpotential of the first layer is less than that of the second layer. Thecatalytic dipole formed as such has an electric potential between thatof the first layer and that of the second layer.

The electrical voltage required for this oxidation is advantageouslyless than the electrolysis voltage, which avoids this latter reactionfrom having to intervene.

According to a non-restricted embodiment, these two layers can becomprised of metal materials from the platinum, gold, ruthenium,rhodium, palladium, silver, nickel cobalt family.

A cationic membrane 230 separates the anode 220 from the cathode 240.According to an embodiment linked to the embodiment describing amineralised solution of peroxide, this membrane only allows the H⁺cations to pass.

The hydrogen ions associated with electrons make it possible to obtainatoms of hydrogen or dihydrogen H₂ on the cathode 240 where the reducingof the H⁺ cations into dihydrogen H₂ is carried out. To do this, thecathode has a porous electrical conductor 241.

As shown in the drawing of FIG. 1, the hydrogen produced is stored in atank 300 and the oxygen, the water and the remainder of hydrogenperoxide are directed to a recovery cell 400.

This recovery cell 400 directs the oxygen to a treatment unit 500 and toa tank 600 for storing the oxygen treated. This oxygen storage tank 600is connected to the oxygen masks 700 of the aircraft.

The water and the remainder of hydrogen peroxide are directed to aremineralisation cell 800 which corrects the mineralisation of the waterthat is going to pass through the filters 910 that are associated andplaced upstream of the valves 900 of the drinking water network of theaircraft.

These filters 910 provide for the destruction of the hydrogen peroxide.

It appears that the first phase of the method makes it possible to haveoxygen as desired by electrically powering the cell 200. It also appearsthat it is no longer necessary to have a tank of drinking water sincethe solution of peroxide cleared of its peroxide will be used asdrinking water once it is remineralised. In addition, the remainder ofunoxidized peroxide is neutralised only at the end of the network, whichmakes it possible to benefit from the biocide characteristics of thehydrogen peroxide which will optimise the treatment of the network bypreventing the presence of bacteria.

The second phase of the method is a phase of producing power by a fuelcell principle by using the hydrogen produced as a reducer and thehydrogen peroxide stored in the tank 100 as an oxidant.

As such, as shown in the drawing of FIG. 2, the solution of hydrogenperoxide P stored in the tank 100 is conveyed to the cell 200 which isthen a reversible cell or an independent cell and which behaves as afuel cell such as shown by the diagram of FIG. 4 where the arrow F3symbolises the H₂O₂ and H₂O solution.

The oxidation of the dihydrogen and the reduction of the hydrogenperoxide allow for the creation of an electrical current coming from thefollowing reactions:

H₂→2H⁺+2e ⁻

H₂O₂+2e ⁻+2H⁺→2H₂O

As described hereinabove the fuel cell also produces water. The arrow F4therefore symbolises this solution containing a remainder of peroxidei.e. H₂O₂ (at a lower concentration) and H₂O. This water onceremineralised associated with the water of the solution supplies thevalves 900. In addition, as with the supply phase, the remainder ofperoxide that was not reduced is neutralised upstream of valves 900.

It appears as such that the second phase of the method allows for theproduction of electricity in the aircraft A.

As an example, the anodic oxidation voltage of the hydrogen peroxide canbe 0.8 volt and the voltage of the fuel cell of the invention can be 1.8volts.

The drawing of FIG. 5 shows a vehicle V receiving an embodiment of adevice implementing the method of the invention. The tank 100′ is filledwith hydrogen peroxide P. For such an application, the first phase ofthe method is above all used to produce the hydrogen that will be storedin the tank 300′. Indeed, the water coming from the solution is not asuseful but could be useful for a vehicle carrying many passengers over along distance. In addition, the oxygen can be partially introduced intothe passenger compartment by means of a mouth 700′.

The hydrogen produced will allow for the implementation of the fuel cell200′ in association with the hydrogen peroxide. The electricity producedallows for the supplying of the means of motorisation of the vehicle V.

The water produced by the first and the second phase of the method isneutralised and returned to the tank 100′ which is compartmentalised forthis purpose. A drain valve 130′ is associated to this compartment.

It is understood that the method and the device, which have just beendescribed and shown hereinabove, were described and shown for thepurposes of a disclosure rather than a limitation. Of course, variousarrangements, modifications and improvements can be made to the examplehereinabove, without however leaving the scope of the invention.

1. Method of managing fluids required to operate a vehicle,characterised by the fact that it comprises an operation of the anodicoxidation of a solution of hydrogen peroxide (P) for the purpose ofproducing oxygen, water and hydrogen cations by subjecting said solutionto an electric current produced by an electrical power source.
 2. Methodaccording to claim 1, characterised by the fact that it comprises anoperation of cathodic reduction of the hydrogen cations coming from saidoperation of anodic oxidation for the purpose of producing dihydrogen.3. Method according to claim 1, characterised by the fact that itcomprises an operation of filling with a solution of hydrogen peroxide(P) a tank (100) carried by the vehicle (A).
 4. Method according toclaim 2, characterised by the fact that it comprises an operation ofstoring the hydrogen produced.
 5. Method according to claim 2,characterised by the fact that it comprises an operation of oxidisingthe hydrogen produced combined with an operation of reducing thehydrogen peroxide (P) for the purpose of producing electricity andwater.
 5. Method according to claim 1, characterised by the fact that itcomprises an operation of treating the oxygen produced.
 6. Methodaccording to claim 1, characterised by the fact that it comprises anoperation of remineralising the water produced.
 7. Method according toclaim 1, characterised by the fact that it comprises an operation ofneutralising the hydrogen peroxide still present in the water.
 8. Methodaccording to claim 1 wherein the vehicle comprises a drinking watertank, characterised by the fact that it comprises an operation offilling the drinking water tank (100) with a solution of hydrogenperoxide (P).
 9. Method according to claim 1, characterised in that theelectrical power required for the anodic oxidation of the hydrogenperoxide comes from the electricity produced during the take-off of theaircraft or during the flight at the cruising speed of the aircraft. 10.Method according to claim 1, characterised in that the water of thesolution of hydrogen peroxide (P) is mineralised.
 11. Method accordingto claim 1, characterised in that the concentration of hydrogen peroxide(P) in the solution is between ten and seventy percent.
 12. Devicemaking it possible to implement the method according to claims 1 and 2,characterised by the fact that it comprises an oxidation cell (200)that, comprising said source of electrical power, is provided with ananode (220) wherein said oxidation takes place and a cathode (240)separated by a cationic membrane (230) that allows only the (H⁺) ions topass, with the positive pole of the source of power being connected tothe anode.
 13. Device according to claim 11, characterised by the factthat said anode (220) comprises several layers: a first porous layer(221) containing a catalyst for producing anodic oxidation (e⁻)electrons, a second porous layer (222) containing a catalyst forcapturing anodic oxidation electrons (e⁻), and a non-porous electricalconductor (223) electrically insulated on the face in contact with thefirst layer and on the face in contact with the hydrogen peroxide (P).